19 research outputs found

    Validation and Normative Data on the Verbal Fluency Test in a Peruvian Population Ranging from Pediatric to Elderly Individuals

    Get PDF
    In neuropsychological evaluation, verbal fluency is a crucial measure of cognitive function, but this measure requires standardized and normative data for use. The present study aimed to obtain validation and normative data for the verbal fluency task in the Peruvian population, with participants ranging from 6 to 94 years and varying in age, educational level, and sex. We recruited 2602 healthy individuals and used linear regression analysis to determine the effect of age, sex, and educational level. We also evaluated internal consistency between categories and phonological tasks with Cronbach's alpha and Pearson's correlation analysis and calculated test-retest reliability after three months. We found significant effects of age, educational level, and sex on phonological and semantic fluency. Participants with more than 12 years of education had the highest scores overall. Regarding age, middle-aged participants (between 31 and 40 years old) had the highest scores; scores gradually decreased outside of this age range. Regarding sex, men performed better than women. These results will increase the ability of clinicians to precisely determine the degree to which verbal fluency is affected in patients of different ages and educational levels

    Neosexismo y autoconcepto en adolescentes peruanos de educaci贸n b谩sica regular

    Get PDF
    Introduction: Sexism refers to the attitude of prejudice or discriminatory conduct based on the alleged inferiority or difference of women as a group. However, in the last decade the social changes have varied perspective, initiating a stage of acceptance and differentiation from concept to neosexism. The neosexism is a manifestation of a conflict between equalitarian values and residual negative feelings toward women. Several investigations indicate their relation to the formation of self-concept among adolescents. Objective: The aim of this research is to establish a relationship between self-concept and neosexism in adolescents. Method: It is a quantitative research whit an ex post facto design. Sample: 350 male and female adolescents aged between 14 and 15 years old in the city of Arequipa. For evaluating, it was used the Neosexism Scale (validity: 0.78 and reliability: 0.58) and the adjectives list for assessing self-concept (Validity: 0.71 and reliability: 0.83). Results: The results reflect gender differences in neosexism among adolescents, showing the persistence of discriminatory concepts of men and women.Introducci贸n: Hablar de sexismo hace alusi贸n a la actitud de prejuicio o conducta discriminatoria basada en la supuesta inferioridad o diferencia de las mujeres como grupo. Sin embargo, en la 煤ltima d茅cada los cambios sociales ocurridos han variado la perspectiva, iniciando una etapa de aceptaci贸n y diferenciaci贸n del concepto al t茅rmino neosexismo. El neosexismo no es sino la manifestaci贸n de un conflicto entre los valores igualitarios y los sentimientos residuales negativos hacia las mujeres. Diversas investigaciones se帽alan su relaci贸n con la formaci贸n del autoconcepto entre los adolescentes. Objetivo: Establecer la relaci贸n existente entre neosexismo y autoconcepto en adolescentes. M茅todo: La investigaci贸n es de tipo cuantitativo con un dise帽o expostfacto. Muestra: Estuvo conformada por 350 adolescentes varones y mujeres entre 14 y 15 a帽os de edad de la ciudad de Arequipa. Para la evaluaci贸n, se utiliz贸 la Escala de neosexismo (validez: 0.78 y confiabilidad: 0.58) y listado de adjetivos para la evaluaci贸n de autoconcepto (Validez: 0.71 y confiabilidad: 0.83). Resultados: Se reflejan diferencias de g茅nero en neosexismo entre los adolescentes; evidenciando la persistencia de concepciones discriminatorias entre hombres y mujeres

    Impact of sociodemographic features and lifestyle on cognitive performance of Peruvian adults

    Get PDF
    Background: Cognitive impairment and dementia may result from a combination of modifiable and nonmodifiable risk and protective factors, such as the environment, educational attainment, time devoted to cognitively stimulating activities, and physical activity. Objective: This study aimed to investigate the mediating role of sociodemographic characteristics and lifestyle factors in the years of education and cognitive performance in Peruvian adults. Methods: This cross-sectional study included 1,478 subjects assessed by Addenbrooke鈥檚 Cognitive Examination Revised (ACE-R). Using mediation models, we evaluated the mediation role of parents鈥 educational level, reading time (RT), and physical activity time (PAT) in the years of education (IYE) and cognitive performance. Results: People who reported having lived in an urban area during their childhood are estimated to have, on average, 2.085 years more formal education than those who lived in rural areas. In addition, 49% of cognitive performance scores are explained by the mediation effect of reading and physical activity time in the IYE. This implies that higher levels of education, mediated by RT and PAT per week, are 1.596 units associated with higher scores on the ACE-R. Conclusion: Despite the fact that nonmodifiable factors (i.e., childhood residence area, parents鈥 educational level) seem to exert an effect on older adults鈥 cognition, their influence is mediated by other factors that are indeed modifiable (i.e., reading time, physical activity engagement). In this sense, lifestyle changes could help prevent or decrease the risk of cognitive impairment and reduce the disease鈥檚 impact on vulnerable environments in Latin American and Caribbean countries

    Social Cognition and Executive Function Impairment in Young Women with Anorexia Nervosa

    Get PDF
    Anorexia nervosa (AN) is a very debilitating disorder and has shown different cognitive deficit patterns. Some of them are controversial because they relate some deficit with autistic traits. Both, social cognition and executive function are top-down processes that regulate social interaction and adaptive behavior in a complex world. Neurocognitive profiles focused on this process are especially useful as endophenotypes in clinic research and intervention.The aims of this study are (1) assessing the contribution of social cognition and executive function to socio-emotional and neurocognitive patterns in anorexia nervosa and (2) investigating the possible relationships between social cognition tasks and executive function measures and clinic features in this eating disorder. Fifteen adolescents with anorexia nervosa and 15 healthy controls took part in this study. Patients were diagnosed with DSM-IV-R criteria. They had suffered the disease for 3 years (SD 卤 1.47). They were compared in social cognition (Reading the Mind in the Eyes and the IOWA Gambling Task) and executive function (verbal fluency tasks, trail making test, and digit span test [DST] from the WAIS-III). The results show that there was a significant difference in social cognition, at the theory of mind and the IOWA gambling task. Finally, for the executive function task, adolescents with AN displayed significant differences in both direct DST and inverse DST, as well as in semantic fluency and phonological fluency compared with controls. These domains show different highly-significant relationships that could explain neurocognitive profiles. In conclusion, many differences were found between adolescents with AN and healthy controls. AN patients displayed important deficits in theory of mind recognition, executive function, and decision making. These deficits could play a role in maintaining pathological patterns and also important endophenotypes in research and intervention might be considered

    Prevalencia de patolog铆a dual en el sur del Per煤: estudio cl铆nico-descriptivo

    Get PDF
    Comorbidity between substance use disorders and other psychiatric disorders or dual diagnosis (PD) is characterized by difficulty in their therapeutic approach, constant relapses and hospital admissions, as well as higher violent and criminal behavior. Our objective was to determine the prevalence of PD in individuals treated at a psychiatric center in Arequipa, Peru. It is a descriptive epidemiological study based on analysis of 445 case histories (HC) of patients admitted during the period of three years (2011-2013). Socio-demographic and clinical characteristics of subjects by comparing those who had a diagnosis of PD, with those who had a diagnosis just by consuming psychotropic substances were established. The results show a prevalence of dual diagnosis in 49%. The average ages were M = 31.45, DS = 15.59 in the with dual diagnosis group CPD and M = 33.93, DS = 15.48 in the without dual diagnosis group SPD; the prevalence of substance use was 51% SPD. Alcohol was the most used substance, followed by cannabis marijuana and cocaine base (PBC). The socio-family and individual vulnerability of the population is evidence for protection or resistance to mental illness, as well as the lack of implementation of effective policies in mental health care for dual disorders, showing worse prognosis and indexes every time higher.La comorbilidad entre un trastorno por uso de sustancias y otros trastornos psiqui谩tricos o patolog铆a dual (PD) se caracteriza por la dificultad en su abordaje terap茅utico, reca铆das constantes e ingresos hospitalarios. Nuestro objetivo fue conocer la prevalencia de PD en un centro psiqui谩trico de Arequipa-Per煤. Es un estudio descriptivo epidemiol贸gico basado en el an谩lisis de 445 historias cl铆nicas (HC) de pacientes ingresados durante el lapso de tres a帽os (periodo 2011-2013). Se establecieron caracter铆sticas sociodemogr谩ficas y cl铆nicas de los sujetos comparando entre quienes presentaron un diagn贸stico de PD, con aquellos que solo tuvieron diagn贸stico por consumo de sustancias psic贸tropas. Los resultados evidencian una prevalencia de patolog铆a dual de 49%. Las edades promedio fueron de M = 31.45, DE = 15.59 en el grupo con patolog铆a dual (CPD) y M = 33.93, DE = 15.48 en el grupo sin patolog铆a dual (SPD); la prevalencia del consumo de sustancias SPD fue del 51%. El alcohol fue la sustancia m谩s consumida, seguida de cannabis, marihuana y la pasta b谩sica de coca铆na (PBC). Se evidencia la vulnerabilidad socio-familiar e individual de la poblaci贸n en cuanto a protecci贸n o resistencia frente a la enfermedad mental, adem谩s de la carencia de pol铆ticas efectivas en salud mental, que muestran peor pron贸stico e 铆ndices cada vez m谩s elevados

    Episodic memory dysfunction and hypersynchrony in brain functional networks in cognitively intact subjects and MCI: A study of 379 individuals

    Get PDF
    Delayed recall (DR) impairment is one of the most significant predictive factors in defining the progression to Alzheimer鈥檚 disease (AD). Changes in brain functional connectivity (FC) could accompany this decline in the DR performance even in a resting state condition from the preclinical stages to the diagnosis of AD itself, so the characterization of the relationship between the two phenomena has attracted increasing interest. Another aspect to contemplate is the potential moderator role of the APOE genotype in this association, considering the evidence about their implication for the disease. 379 subjects (118 mild cognitive impairment (MCI) and 261 cognitively intact (CI) individuals) underwent an extensive evaluation, including MEG recording. Applying cluster-based permutation test, we identified a cluster of differences in FC and studied which connections drove such an effect in DR. The moderation effect of APOE genotype between FC results and delayed recall was evaluated too. Higher FC in beta band in the right occipital region is associated with lower DR scores in both groups. A significant anteroposterior link emerged in the seed-based analysis with higher values in MCI. Moreover, APOE genotype appeared as a moderator between beta FC and DR performance only in the CI group. An increased beta FC in the anteroposterior brain region appears to be associated with lower memory performance in MCI. This finding could help discriminate the pattern of the progression of healthy aging to MCI and the relation between resting state and memory performance

    Resting-State Beta-Band Recovery Network Related to Cognitive Improvement After Stroke

    Get PDF
    Stroke is the second leading cause of death worldwide and it causes important long-term cognitive and physical deficits that hamper patients' daily activity. Neuropsychological rehabilitation (NR) has increasingly become more important to recover from cognitive disability and to improve the functionality and quality of life of these patients. Since in most stroke cases, restoration of functional connectivity (FC) precedes or accompanies cognitive and behavioral recovery, understanding the electrophysiological signatures underlying stroke recovery mechanisms is a crucial scientific and clinical goal. For this purpose, a longitudinal study was carried out with a sample of 10 stroke patients, who underwent two neuropsychological assessments and two resting-state magnetoencephalographic (MEG) recordings, before and after undergoing a NR program. Moreover, to understand the degree of cognitive and neurophysiological impairment after stroke and the mechanisms of recovery after cognitive rehabilitation, stroke patients were compared to 10 healthy controls matched for age, sex, and educational level. After intra and inter group comparisons, we found the following results: (1) Within the stroke group who received cognitive rehabilitation, almost all cognitive domains improved relatively or totally; (2) They exhibit a pattern of widespread increased in FC within the beta band that was related to the recovery process (there were no significant differences between patients who underwent rehabilitation and controls); (3) These FC recovery changes were related with the enhanced of cognitive performance. Furthermore, we explored the capacity of the neuropsychological scores before rehabilitation, to predict the FC changes in the brain network. Significant correlations were found in global indexes from the WAIS-III: Performance IQ (PIQ) and Perceptual Organization index (POI) (i.e., Picture Completion, Matrix Reasoning, and Block Design)

    Early diagnosis of Alzheimer' Disease in different cultural backgrounds : Electrophysiological and cognitive biomarkers

    No full text
    L'envelliment 茅s un proc茅s natural que es caracteritza per l'acumulaci贸 progressiva de canvis fisiol貌gics i per enlentir alguns dominis cognitius. Tot i aix貌, alguns aspectes d'aquests canvis cognitius tamb茅 s'associen a estats patol貌gics, com la malaltia d'Alzheimer (MA). La MA 茅s un trastorn neurodegeneratiu progressiu, resultat d'una interacci贸 complexa entre la gen猫tica i els factors ambientals experimentats al llarg de la vida. Una aproximaci贸 per definir el patr贸 del mecanisme biol貌gic subjacent a l'aparici贸 i el desenvolupament de la MA 茅s l'煤s d'eines no invasives que permetin caracteritzar i seguir el desenvolupament de la patologia de la MA des d'estadis precl铆nics. En aquest sentit, l'electroencefalografia (EEG) i la magnetoencefalografia (MEG) s贸n eines 煤tils ja que permeten estudiar l'evoluci贸 dels marcadors electrofisiol貌gics al cervell de manera totalment no invasiva. L'objectiu principal d'aquesta Tesi Doctoral 茅s identificar marcadors electrofisiol貌gics i cognitius robusts que permetin distingir els subjectes sans dels pacients amb deteriorament cognitiu lleu (DCL), considerant com a fonts d'informaci贸 les dades sociodemogr脿fiques, l'avaluaci贸 neuropsicol貌gica, els biomarcadors del l铆quid cefaloraquidi (LCR) i les mesures EEG/MEG extretes de l'activitat en rep貌s de mostres multiculturals. Per aix貌, la tesi s'organitza en dues parts. Pel que fa a l'envelliment saludable, els dos primers estudis inclouen (i) l'an脿lisi de l'impacte de les caracter铆stiques sociodemogr脿fiques i d'estil de vida sobre el rendiment cognitiu en adults peruans i (ii) una revisi贸 sistem脿tica de les troballes pr猫vies sobre l'associaci贸 entre els perfils electrofisiol貌gics en estat de rep貌s i el rendiment cognitiu. Pel que fa a l'envelliment patol貌gic, la tesi inclou (iii) l'exploraci贸 de l'associaci贸 entre el record retardat i la connectivitat funcional en estat de rep貌s en subjectes cognitivament intactes i DCL; (iv) un estudi multic猫ntric dels marcadors del LCR i la seva associaci贸 amb el deteriorament de la mem貌ria epis貌dica i les funcions executives en DCL; i (v) la relaci贸 dels patrons electrofisiol貌gics del DCL amb els biomarcadors del LCR segons el sexe. Els nostres resultats corroboren la rellev脿ncia dels factors no modificables i modificables relacionats amb el deteriorament cognitiu en l'envelliment saludable. A m茅s, des del punt de vista electrofisiol貌gic, la mesura de la freq眉猫ncia del pic alfa s'associa amb el rendiment cognitiu i es podria considerar com un marcador de l'envelliment saludable. D'altra banda, pel que fa al DCL, (i) els valors m茅s alts a la connectivitat funcional de la banda beta a la regi贸 occipital dreta es van associar amb puntuacions m茅s baixes de record retardat en subjectes cognitivament intactes i amb DCL. El cervell sembla perdre progressivament la capacitat de desincronitzar les oscil路lacions beta, i aquest proc茅s comen莽a a ser significatiu a les etapes precl铆niques, almenys en els participants amb vulnerabilitat a la MA, com la pres猫ncia de l'al路lel APOE 蔚4; (ii) un deteriorament primerenc del funcionament executiu, que podria afectar en 煤ltima inst脿ncia el seu rendiment a la prova de mem貌ria epis貌dica, podria ajudar a discriminar entre dos patrons diferents de DCL; i (iii) hi ha una possible associaci贸 diferencial entre els perfils EEG i els marcadors del LCR en els homes i les dones. Aquesta troballa podria ser la base per donar suport a la implementaci贸 d'iniciatives que fomentin un estil de vida saludable i promoguin activitats de salut cerebral que afavoreixin la reducci贸 del deteriorament cognitiu a l'envelliment i reforcen la necessitat de realitzar assajos cl铆nics m茅s personalitzats per millorar la detecci贸 primerenca de la MA fent 煤s de les t猫cniques de neuroimatge.El envejecimiento es un proceso natural que se caracteriza por la acumulaci贸n progresiva de cambios fisiol贸gicos y la ralentizaci贸n de algunos dominios cognitivos. Sin embargo, algunos aspectos de estos cambios cognitivos tambi茅n se asocian a estados patol贸gicos, como la enfermedad de Alzheimer (EA). La EA es un trastorno neurodegenerativo progresivo, resultado de una compleja interacci贸n entre la gen茅tica y los factores ambientales experimentados a lo largo de la vida. Una aproximaci贸n para definir el patr贸n del mecanismo biol贸gico que subyace a la aparici贸n y desarrollo de la EA es el uso de herramientas no invasivas que permitan caracterizar y seguir el desarrollo de la patolog铆a de la EA desde estadios precl铆nicos. En este sentido, la electroencefalograf铆a (EEG), y la magnetoencefalograf铆a (MEG) son herramientas 煤tiles ya que permiten estudiar la evoluci贸n de los marcadores electrofisiol贸gicos en el cerebro de forma totalmente no invasiva. El objetivo principal de esta Tesis Doctoral es identificar marcadores electrofisiol贸gicos y cognitivos robustos que permitan distinguir a los sujetos sanos de los pacientes con deterioro cognitivo leve (DCL), considerando como fuentes de informaci贸n los datos sociodemogr谩ficos, la evaluaci贸n neuropsicol贸gica, los biomarcadores del l铆quido cefalorraqu铆deo (LCR) y las medidas EEG/MEG extra铆das de la actividad en reposo de muestras multiculturales. Para ello, la tesis se organiza en dos partes. En cuanto al envejecimiento saludable, los dos primeros estudios incluyen (i) el an谩lisis del impacto de las caracter铆sticas sociodemogr谩ficas y de estilo de vida sobre el rendimiento cognitivo en adultos peruanos y (ii) una revisi贸n sistem谩tica de los hallazgos previos sobre la asociaci贸n entre los perfiles electrofisiol贸gicos en estado de reposo y el rendimiento cognitivo. En relaci贸n con el envejecimiento patol贸gico, la tesis incluye (iii) la exploraci贸n de la asociaci贸n entre el recuerdo retardado y la conectividad funcional en estado de reposo en sujetos cognitivamente intactos y DCL; (iv) un estudio multic茅ntrico de los marcadores del LCR y su asociaci贸n con el deterioro de la memoria epis贸dica y las funciones ejecutivas en DCL; y (v) la relaci贸n de los patrones electrofisiol贸gicos del DCL con los biomarcadores del LCR seg煤n el sexo. Nuestros resultados corroboran la relevancia de los factores no modificables y modificables relacionados con el deterioro cognitivo en el envejecimiento saludable. Adem谩s, desde el punto de vista electrofisiol贸gico, la medida de la frecuencia del pico alfa se asocia con el rendimiento cognitivo y podr铆a considerarse como un marcador del envejecimiento saludable. Por otro lado, en lo que respecta al DCL, (i) los valores m谩s altos en la conectividad funcional de la banda beta en la regi贸n occipital derecha se asociaron con puntuaciones m谩s bajas de recuerdo retardado en sujetos cognitivamente intactos y con DCL. El cerebro parece perder progresivamente la capacidad de desincronizar las oscilaciones beta, y este proceso empieza a ser significativo en las etapas precl铆nicas, al menos en los participantes con vulnerabilidad a la EA, como la presencia del alelo APOE 蔚4; (ii) un deterioro temprano del funcionamiento ejecutivo, que podr铆a afectar en 煤ltima instancia a su rendimiento en la prueba de memoria epis贸dica, podr铆a ayudar a discriminar entre dos patrones diferentes de DCL; y (iii) existe una posible asociaci贸n diferencial entre los perfiles EEG y los marcadores del LCR en los hombres y mujeres. Este hallazgo podr铆a ser la base para apoyar la implementaci贸n de iniciativas que fomenten un estilo de vida saludable y promuevan actividades de salud cerebral que favorezcan la reducci贸n del deterioro cognitivo en el envejecimiento y refuerzan la necesidad de realizar ensayos cl铆nicos m谩s personalizados para mejorar la detecci贸n temprana de la EA haciendo uso de las t茅cnicas de neuroimagen.Aging is a natural process characterized by the progressive accumulation of physiological changes and a slowdown of some cognitive domains. However, some aspects of these cognitive changes are also associated with pathological states, such as the Alzheimer's disease (AD). AD is a progressive neurodegenerative disorder, results of a complex interaction between genetics and environmental factors experienced throughout life. One approach to defining the pattern of the biological mechanism underlying the onset and development of AD is the use of non-invasive tools able to detect changes in the structure and function of the nervous system in humans, which allows characterizing and following the development of AD pathology from preclinical stages. In this sense, electroencephalography (EEG), and magnetoencephalography (MEG) are useful tools since they allow studying the evolution of electrophysiological markers in the brain in a completely non-invasive way. The combined use of these techniques, evaluation brain activity in resting-state, with neuropathological markers of AD and cognitive performance, could help to improve the distinguish pattern of early AD. The main objective of this Doctoral Thesis is to identify robust electrophysiological and cognitive markers that allow to distinguish healthy subjects from patients with mild cognitive impairment (MCI), considering as sources of information sociodemographic data, neuropsychological assessment, cerebrospinal fluid (CSF) biomarkers, and EEG/MEG measures extracted from resting activity of multicultural samples. For this purpose, the thesis is organized into two parts focusing on the study of healthy and pathological aging. Regarding healthy aging, the first two studies include (i) the analysis of the impact of sociodemographic and lifestyle characteristics on cognitive performance in Peruvian adults and (ii) a systematic review of previous findings on the association between resting-state electrophysiological profiles and cognitive performance in healthy aging. Concerning pathological aging, the thesis includes (iii) the exploration of the potential association between delayed recall performance and resting-state functional connectivity in cognitively intact subjects and MCI patients; (iv) a multicenter study of CSF markers and their association with episodic memory impairment and executive functions in patients with MCI; and (v) the relationship of electrophysiological signs of MCI with CSF biomarkers and the assessment of this relationship according to sex. Our findings corroborate the relevance of non-modifiable and modifiable factors related with cognitive decline in healthy aging. Although nonmodifiable factors impact older adults' cognition, their influence is mediated by other factors that are indeed modifiable (i.e., time spend reading, engagement in physical activity). Furthermore, since electrophysiological point of view, the measure of alpha peak frequency is associated with the cognitive performance and could be considered as an electrophysiological marker of healthy aging. On the other hand, regarding the electrophysiological profile of MCI, (i) higher values in functional connectivity of the beta band in the right occipital region were associated with lower delayed recall scores in cognitively intact and MCI subjects. The brain seems to progressively lose the ability to desynchronize beta oscillations, and this process starts to become significant in preclinical stages, at least in participants with AD vulnerability such as the presence of the APOE 蔚4 allele; (ii) an early executive functioning impairment, which could ultimately affect their performance on episodic memory test could help to discriminate between two different patterns of MCI; and (iii) there is a potential differential association between EEG profiles and CSF markers in male and female participants. This finding could be the base to support the implementation of initiatives encouraging a healthy lifestyle and promoting brain health activities which could favor reducing cognitive decline in aging and reinforce the need for clinical trials focused on a more personalized approach to improve the early detection of AD taking account the neuroimaging techniques

    Early diagnosis of Alzheimer鈥 Disease in different cultural backgrounds: Electrophysiological and cognitive biomarkers

    Get PDF
    L鈥檈nvelliment 茅s un proc茅s natural que es caracteritza per l鈥檃cumulaci贸 progressiva de canvis fisiol貌gics i per enlentir alguns dominis cognitius. Tot i aix貌, alguns aspectes d鈥檃quests canvis cognitius tamb茅 s鈥檃ssocien a estats patol貌gics, com la malaltia d鈥橝lzheimer (MA). La MA 茅s un trastorn neurodegeneratiu progressiu, resultat d鈥檜na interacci贸 complexa entre la gen猫tica i els factors ambientals experimentats al llarg de la vida. Una aproximaci贸 per definir el patr贸 del mecanisme biol貌gic subjacent a l鈥檃parici贸 i el desenvolupament de la MA 茅s l鈥櫭簊 d鈥檈ines no invasives que permetin caracteritzar i seguir el desenvolupament de la patologia de la MA des d鈥檈stadis precl铆nics. En aquest sentit, l鈥檈lectroencefalografia (EEG) i la magnetoencefalografia (MEG) s贸n eines 煤tils ja que permeten estudiar l鈥檈voluci贸 dels marcadors electrofisiol貌gics al cervell de manera totalment no invasiva. L鈥檕bjectiu principal d鈥檃questa Tesi Doctoral 茅s identificar marcadors electrofisiol貌gics i cognitius robusts que permetin distingir els subjectes sans dels pacients amb deteriorament cognitiu lleu (DCL), considerant com a fonts d鈥檌nformaci贸 les dades sociodemogr脿fiques, l鈥檃valuaci贸 neuropsicol貌gica, els biomarcadors del l铆quid cefaloraquidi (LCR) i les mesures EEG/MEG extretes de l鈥檃ctivitat en rep貌s de mostres multiculturals. Per aix貌, la tesi s鈥檕rganitza en dues parts. Pel que fa a l鈥檈nvelliment saludable, els dos primers estudis inclouen (i) l鈥檃n脿lisi de l鈥檌mpacte de les caracter铆stiques sociodemogr脿fiques i d鈥檈stil de vida sobre el rendiment cognitiu en adults peruans i (ii) una revisi贸 sistem脿tica de les troballes pr猫vies sobre l鈥檃ssociaci贸 entre els perfils electrofisiol貌gics en estat de rep貌s i el rendiment cognitiu. Pel que fa a l鈥檈nvelliment patol貌gic, la tesi inclou (iii) l鈥檈xploraci贸 de l鈥檃ssociaci贸 entre el record retardat i la connectivitat funcional en estat de rep貌s en subjectes cognitivament intactes i DCL; (iv) un estudi multic猫ntric dels marcadors del LCR i la seva associaci贸 amb el deteriorament de la mem貌ria epis貌dica i les funcions executives en DCL; i (v) la relaci贸 dels patrons electrofisiol貌gics del DCL amb els biomarcadors del LCR segons el sexe. Els nostres resultats corroboren la rellev脿ncia dels factors no modificables i modificables relacionats amb el deteriorament cognitiu en l鈥檈nvelliment saludable. A m茅s, des del punt de vista electrofisiol貌gic, la mesura de la freq眉猫ncia del pic alfa s鈥檃ssocia amb el rendiment cognitiu i es podria considerar com un marcador de l鈥檈nvelliment saludable. D鈥檃ltra banda, pel que fa al DCL, (i) els valors m茅s alts a la connectivitat funcional de la banda beta a la regi贸 occipital dreta es van associar amb puntuacions m茅s baixes de record retardat en subjectes cognitivament intactes i amb DCL. El cervell sembla perdre progressivament la capacitat de desincronitzar les oscil路lacions beta, i aquest proc茅s comen莽a a ser significatiu a les etapes precl铆niques, almenys en els participants amb vulnerabilitat a la MA, com la pres猫ncia de l鈥檃l路lel APOE 蔚4; (ii) un deteriorament primerenc del funcionament executiu, que podria afectar en 煤ltima inst脿ncia el seu rendiment a la prova de mem貌ria epis貌dica, podria ajudar a discriminar entre dos patrons diferents de DCL; i (iii) hi ha una possible associaci贸 diferencial entre els perfils EEG i els marcadors del LCR en els homes i les dones. Aquesta troballa podria ser la base per donar suport a la implementaci贸 d鈥檌niciatives que fomentin un estil de vida saludable i promoguin activitats de salut cerebral que afavoreixin la reducci贸 del deteriorament cognitiu a l鈥檈nvelliment i reforcen la necessitat de realitzar assajos cl铆nics m茅s personalitzats per millorar la detecci贸 primerenca de la MA fent 煤s de les t猫cniques de neuroimatge.El envejecimiento es un proceso natural que se caracteriza por la acumulaci贸n progresiva de cambios fisiol贸gicos y la ralentizaci贸n de algunos dominios cognitivos. Sin embargo, algunos aspectos de estos cambios cognitivos tambi茅n se asocian a estados patol贸gicos, como la enfermedad de Alzheimer (EA). La EA es un trastorno neurodegenerativo progresivo, resultado de una compleja interacci贸n entre la gen茅tica y los factores ambientales experimentados a lo largo de la vida. Una aproximaci贸n para definir el patr贸n del mecanismo biol贸gico que subyace a la aparici贸n y desarrollo de la EA es el uso de herramientas no invasivas que permitan caracterizar y seguir el desarrollo de la patolog铆a de la EA desde estadios precl铆nicos. En este sentido, la electroencefalograf铆a (EEG), y la magnetoencefalograf铆a (MEG) son herramientas 煤tiles ya que permiten estudiar la evoluci贸n de los marcadores electrofisiol贸gicos en el cerebro de forma totalmente no invasiva. El objetivo principal de esta Tesis Doctoral es identificar marcadores electrofisiol贸gicos y cognitivos robustos que permitan distinguir a los sujetos sanos de los pacientes con deterioro cognitivo leve (DCL), considerando como fuentes de informaci贸n los datos sociodemogr谩ficos, la evaluaci贸n neuropsicol贸gica, los biomarcadores del l铆quido cefalorraqu铆deo (LCR) y las medidas EEG/MEG extra铆das de la actividad en reposo de muestras multiculturales. Para ello, la tesis se organiza en dos partes. En cuanto al envejecimiento saludable, los dos primeros estudios incluyen (i) el an谩lisis del impacto de las caracter铆sticas sociodemogr谩ficas y de estilo de vida sobre el rendimiento cognitivo en adultos peruanos y (ii) una revisi贸n sistem谩tica de los hallazgos previos sobre la asociaci贸n entre los perfiles electrofisiol贸gicos en estado de reposo y el rendimiento cognitivo. En relaci贸n con el envejecimiento patol贸gico, la tesis incluye (iii) la exploraci贸n de la asociaci贸n entre el recuerdo retardado y la conectividad funcional en estado de reposo en sujetos cognitivamente intactos y DCL; (iv) un estudio multic茅ntrico de los marcadores del LCR y su asociaci贸n con el deterioro de la memoria epis贸dica y las funciones ejecutivas en DCL; y (v) la relaci贸n de los patrones electrofisiol贸gicos del DCL con los biomarcadores del LCR seg煤n el sexo. Nuestros resultados corroboran la relevancia de los factores no modificables y modificables relacionados con el deterioro cognitivo en el envejecimiento saludable. Adem谩s, desde el punto de vista electrofisiol贸gico, la medida de la frecuencia del pico alfa se asocia con el rendimiento cognitivo y podr铆a considerarse como un marcador del envejecimiento saludable. Por otro lado, en lo que respecta al DCL, (i) los valores m谩s altos en la conectividad funcional de la banda beta en la regi贸n occipital derecha se asociaron con puntuaciones m谩s bajas de recuerdo retardado en sujetos cognitivamente intactos y con DCL. El cerebro parece perder progresivamente la capacidad de desincronizar las oscilaciones beta, y este proceso empieza a ser significativo en las etapas precl铆nicas, al menos en los participantes con vulnerabilidad a la EA, como la presencia del alelo APOE 蔚4; (ii) un deterioro temprano del funcionamiento ejecutivo, que podr铆a afectar en 煤ltima instancia a su rendimiento en la prueba de memoria epis贸dica, podr铆a ayudar a discriminar entre dos patrones diferentes de DCL; y (iii) existe una posible asociaci贸n diferencial entre los perfiles EEG y los marcadores del LCR en los hombres y mujeres. Este hallazgo podr铆a ser la base para apoyar la implementaci贸n de iniciativas que fomenten un estilo de vida saludable y promuevan actividades de salud cerebral que favorezcan la reducci贸n del deterioro cognitivo en el envejecimiento y refuerzan la necesidad de realizar ensayos cl铆nicos m谩s personalizados para mejorar la detecci贸n temprana de la EA haciendo uso de las t茅cnicas de neuroimagen.Aging is a natural process characterized by the progressive accumulation of physiological changes and a slowdown of some cognitive domains. However, some aspects of these cognitive changes are also associated with pathological states, such as the Alzheimer鈥檚 disease (AD). AD is a progressive neurodegenerative disorder, results of a complex interaction between genetics and environmental factors experienced throughout life. One approach to defining the pattern of the biological mechanism underlying the onset and development of AD is the use of non-invasive tools able to detect changes in the structure and function of the nervous system in humans, which allows characterizing and following the development of AD pathology from preclinical stages. In this sense, electroencephalography (EEG), and magnetoencephalography (MEG) are useful tools since they allow studying the evolution of electrophysiological markers in the brain in a completely non-invasive way. The combined use of these techniques, evaluation brain activity in resting-state, with neuropathological markers of AD and cognitive performance, could help to improve the distinguish pattern of early AD. The main objective of this Doctoral Thesis is to identify robust electrophysiological and cognitive markers that allow to distinguish healthy subjects from patients with mild cognitive impairment (MCI), considering as sources of information sociodemographic data, neuropsychological assessment, cerebrospinal fluid (CSF) biomarkers, and EEG/MEG measures extracted from resting activity of multicultural samples. For this purpose, the thesis is organized into two parts focusing on the study of healthy and pathological aging. Regarding healthy aging, the first two studies include (i) the analysis of the impact of sociodemographic and lifestyle characteristics on cognitive performance in Peruvian adults and (ii) a systematic review of previous findings on the association between resting-state electrophysiological profiles and cognitive performance in healthy aging. Concerning pathological aging, the thesis includes (iii) the exploration of the potential association between delayed recall performance and resting-state functional connectivity in cognitively intact subjects and MCI patients; (iv) a multicenter study of CSF markers and their association with episodic memory impairment and executive functions in patients with MCI; and (v) the relationship of electrophysiological signs of MCI with CSF biomarkers and the assessment of this relationship according to sex. Our findings corroborate the relevance of non-modifiable and modifiable factors related with cognitive decline in healthy aging. Although nonmodifiable factors impact older adults鈥 cognition, their influence is mediated by other factors that are indeed modifiable (i.e., time spend reading, engagement in physical activity). Furthermore, since electrophysiological point of view, the measure of alpha peak frequency is associated with the cognitive performance and could be considered as an electrophysiological marker of healthy aging. On the other hand, regarding the electrophysiological profile of MCI, (i) higher values in functional connectivity of the beta band in the right occipital region were associated with lower delayed recall scores in cognitively intact and MCI subjects. The brain seems to progressively lose the ability to desynchronize beta oscillations, and this process starts to become significant in preclinical stages, at least in participants with AD vulnerability such as the presence of the APOE 蔚4 allele; (ii) an early executive functioning impairment, which could ultimately affect their performance on episodic memory test could help to discriminate between two different patterns of MCI; and (iii) there is a potential differential association between EEG profiles and CSF markers in male and female participants. This finding could be the base to support the implementation of initiatives encouraging a healthy lifestyle and promoting brain health activities which could favor reducing cognitive decline in aging and reinforce the need for clinical trials focused on a more personalized approach to improve the early detection of AD taking account the neuroimaging techniques.Universitat Aut貌noma de Barcelona. Programa de Doctorat en Neuroci猫ncie
    corecore